I agree with Nancy--the mail carrier will likely freak out, not only from curiosity, but from concern if not downright fear. Instead of making the red flag go up on the box, why not just install some motion sensing or other devices like some country people use for being notified that someone's at the gate at the end of a long driveway, or that bears are raiding the orchard? You get an audio signal inside your house, alarming no one but you.

As father of precocious 6 and 2 year olds, I recognize how my perspective has changed in the past, say, 6 years.

In olden tymes, my reaction probably would've been. Yeah, neat lid.

Nowadays, my response goes like this:

wow!

daughter gets an idea to make something

... and takes initiative to do something

... and solicits Dad's assist

... and Dad steps up to the plate

... and little sister gets involved

... and Mom gets involved to take the idea from an animated shoebox (yes, I'm intentionally being disparaging here, albeit in a light-hearted way) and shepherd it into a product with immediate appeal outside the gearhead community.

This is a Truly Great Family Thing that needs to be savored and put in the scrapbook.

I guess your kids are a little old for this, so you'll have to modify appropriately, but I'd say:

Kudos to the whole family, and Happy Meals all around for Saturday dinner.

p.s. Jeremy: some hombre-a-hombre advice, I don't recommend showing this article to your Better Half until you do some revisionist editing and give full productization credit appropriately. I'll go out on a sexist limb here, but with this whole "family" thing, women eat this shtuff up. Know what I mean? (nudge nudge: You might have some more dividends to harvest, even if they would only be as "Keep Jeremy out of the Doghouse" insurance.)

Wow! So what I'm thinking is back in the "olden days," kids were much more handy with natural raw materials, and now they are much more handy with technology. Not sure what happened to my generation! (Though truth be told, some of the kids were really good with electronics at the time; I am just wasn't born with the mechanical or builder gene. :))

This is just, well, cute as heck. I remember the cardboard versions of Valentine's mailboxes from elementary school, and these actually resemble those a lot except for the materials, and obviously the electronics. What a dad!

Bob, I think you are on the right track with a mechanical solution. A web site called themailsig dot com shows a red ball on a chain that falls when someone opens the mail box. After falling it hangs about 12 inches below the box so you can see it from the house. Probably cheaper than a torsion spring and postmaster approved according to the site. Plus you get to make cracks about "the old ball and chain"!

You'll still probably freak out your mail carrier, Bob. If it was me and I saw a flag moving upward on its own - I would definitely be curious, if not concerned. I would love to see the expression on their face! And their schedules change in our neighborhood so you may have the opportunity to startle multiple carriers. Unfortunately since the Postal Service is a federal agency with a multitude of rules and regs, they may not appreciate you assigning a different job to their flag...

This story is going to be a big help to me at home. My mailbox is on the street about 150 feet from my house, and with the various letter carriers comming at different times, me and my lazy butt hate walking to the box and finding it empty. For years I've been complentating a mechanial device with a torsion spring to stand up the red flag when the letter carrier opens the front door. A suitable trigger arrangement would obviously work, but I was afraid that the shock of the flag popping up would scare the mail person resulting in some sort of liability on my part. With a small motor slowly erecting the flag, there should be nothing to scare him. Yes, I know the red flag is supposed to indicate that outgoing mail is in the box to be picked up. I wonder if there's a Postal Service rule on this matter?

I agree Rathomas - the accessibility and affordability is very exciting. Not only Radio Shack - but being able to order development kits off of the internet at reasonable prices is very nice. I just bought hubby a PIC student development kit for his birthday - it is way cool - I think I will be playing with it too!

Nancy & William - To a young person without much understanding of electronics, using a modern microcontroller can be much more, um, plug-and-play. In the course of interfacing the servo and the light sensor, they still have an opportunity to discuss and learn some very basic electronics, enough to potentially spark an interest in hardware OR software OR (my favorite) BOTH!

I'm excited about today's technical environment and the renewed and improved accessibility of both electronics and software to a young hobbyist. Just 15 or so years ago I was lamenting the impending fall of electronics as a hobby (or gateway drug ;) for youngsters. I'd cite things like the prevalence of surface mount components, lack of accessible/affordable tools for circuit design, layout and software development. I am so glad that I turned out to be very wrong! Instead, microcontrollers like the AVR and PIC have become easier to use, boards like the Arduino are affordable, easy to get started with and, to be able to do much more than blink an LED or move a servo, they actually encourage electronics tinkering. Scmartboards for surface mount parts and micros still available in thru hole packages mean you don't need a pick and place machine in your bedroom ;)

Heck, even Radio Shack is back to stocking things for real hobby electronics!

Elizabeth: When I was in grammar school, toothpicks had not yet been invented, but one of our teachers suggested that us boys build an American settler house. So, after school we went into the woods, chopped down some trees w/ our fathers' axes, and built a house. It was so well designed that the principal of the school moved his family into it!

Industrial workplaces are governed by OSHA rules, but this isn’t to say that rules are always followed. While injuries happen on production floors for a variety of reasons, of the top 10 OSHA rules that are most often ignored in industrial settings, two directly involve machine design: lockout/tagout procedures (LO/TO) and machine guarding.

Focus on Fundamentals consists of 45-minute on-line classes that cover a host of technologies. You learn without leaving the comfort of your desk. All classes are taught by subject-matter experts and all are archived. So if you can't attend live, attend at your convenience.